1. Field of the Invention
The present invention relates to the field of managing a disk and its defects, and more particularly, to a recording medium for storing defect management information with respect to whether linear replacement is used, a method of effectively managing defects to record and/or reproduce video and/or audio data from a digital versatile disc random access memory (DVD-RAM) in real time, and a method of recording data in real time using defect management information.
2. Description of the Related Art
Real time recording or reproduction means that a given amount of data is necessarily recorded or reproduced within a given time since input information is lost if it is not processed at the moment data is input, and since a phenomenon such as a pause of an image or temporary interruption of music occurs with reproduction of data as abnormal information if data is not recorded or reproduced at a predetermined speed. The above-described problems are caused since the input of information cannot be temporally controlled by a recording and reproducing apparatus.
In the DVD-RAM standard version 1.0, a method of managing defects generated on a disk has been disclosed to increase the reliability of data recorded on the disk. Slipping replacement and linear replacement are included as the disclosed defect management methods: the first method processes defects detected in an initializing process; and the second method replaces an error correction code (ECC) block unit (16-sector unit) including a sector having a defect generated during use of the disc with a defect-free ECC block in a spare area.
The slipping replacement is used to minimize a reduction in the recording or reproduction speed due to defects, in which a logical sector number to be provided to a defective sector is provided to a sector next to the defective sector detected during a certification process for investigating defects of a disc when the disc is initialized, that is, data is recorded or reproduced by slipping a sector on which a defect is generated during recording or reproduction. Here, a real physical sector number is pushed back by the sector number designated by slipping the defective sector. Such a left-behind phenomenon is solved by using as many sectors as there are defects in a spare area located at the end portion of a corresponding user data area.
However, the slipping replacement cannot be used for a defect generated while a disc is used. When a defective portion is disregarded and skipped, discontinuity is generated on logical sector numbering, which means that the slipping replacement violates file system rules. Thus, the linear replacement is used when a defect is generated during use of the disc, which means the replacement of an ECC block including a defective sector with an ECC block existing in a spare area.
When the linear replacement is used, no vacuum exists in a logical sector number, however, the position of a sector on a disc is discontinuous, and real data corresponding to a defective ECC block exists in the spare area.
As described above, when real time recording, in which the time for temporarily-input information cannot be arbitrarily delayed, such as, recording of broadcast information or a real image, is necessary, information is recorded in an area to be linearly-replaced by undergoing a process in which a pickup goes up to the spare area and searches for an area to be linearly replaced, and a process in which the pickup comes back. Hence, the recording speed is reduced, so that information input in real time cannot be continuously recorded when the linear replacement is used.
It is prescribed that a DVD-RAM drive according to the DVD-RAM standard version 1.0 processes all of this defect management to reduce the burden of the host computer used in the drive. The host computer is designed to transmit a command ordered not to manage defects to the drive using a command denoted in an interface standard. That is, if the host computer determines whether defect management will be performed, the defect management itself is supposed to be performed by the drive.
Even when the host computer does not manage defects according to the need of an application program, the DVD-RAM disc according to the DVD-RAM standard version 1.0 must necessarily manage defects recorded in a primary defect list (PDL) and a secondary defect list (SDL) according to a defect management rule if an area slippingly replaced or linearly replaced due to defect management performed by another drive exists. Here, it is prescribed that the position of a defective sector replaced according to slipping replacement should be recorded in the PDL, and the position of a defective block replaced according to linear replacement should be recorded in the SDL. That is, when data is recorded after setting the fact that a specific drive should not perform defect management using the linear replacement, it cannot be ensured that other drives must also not perform the linear replacement on the same disc.
Therefore, when real time recording is performed by a current DVD-RAM disc, it may be difficult because of an area to be used by the linear replacement.